1. Field of the Invention
The present invention relates to airbag module attachment systems. More specifically, the present invention relates to an airbag module attachment system that does not require fastener openings in the cover on the instrument panel.
2. Technical Background
Various occupant restraining systems, such as airbags, have proven effective in preventing injury and death during automobile collisions. As a result, multiple systems are currently being employed in order to adequately restrain a vehicle occupant. One such system is the knee bolstering airbag. A knee bolstering airbag is an airbag module configured to expand or inflate during impact to prevent the occupant from “submarining” or sliding under the steering column. The knee bolstering airbag engages the knees of the occupant to keep the occupant upright and allowing the steering wheel mounted airbag or dashboard mounted airbag to attenuate the occupant's motion.
Knee bolstering airbags are typically mounted in the instrument panel of an automobile. The knee bolstering airbags may be mounted below the steering column or below the passenger side dashboard and are typically visible to the vehicle occupants. Currently, many knee bolstering airbags are attached to the instrument panel through conventional fasteners, such as screws and rivets. However, in order to attach a knee bolstering airbag to an instrument panel with screws or rivets, fastener openings are necessary in the airbag cover. The fastener openings in the covers are required to properly secure the fasteners during attachment of the module to the instrument panel.
Unfortunately, the fastener openings often create a poor appearance in the highly visible instrument panel. Often, four or more fastener openings are required in a cover to securely attach an airbag module. Each additional fastener opening detracts from the overall appearance of the instrument panel. Some attempts to conceal the fastener openings have been made by employing plugs that may be inserted into the fastener openings of the cover. However, while plugs do provide an improved appearance, the covers do not have a uniform smooth surface. Furthermore, during the life of the automobile the plugs may fall out of the fastener openings, again creating a poor appearance.
In order to conceal fastener openings, some fastener openings are being located in the lower portions of the instrument panel, such that the fastener opening are not visible to the vehicle occupants. However, it may not always be possible to position the fastener openings at a location that is not visible to the occupants. Furthermore, positioning the fastener openings below the instrument panel can increase the difficulty in attaching the module to the instrument panel because of the limited workspace.
Another problem with current knee bolstering airbags is the position of the fasteners relative to the airbag. In some instances, the fasteners are positioned directly through the airbag itself. Such fastener configurations require complex openings in the airbag for the fasteners that allow passage of the fastener and inflation of the airbag. Fastener openings in the airbag can increase the cost and complexity of the airbag. Fastener openings in the airbag are particularly problematic with metal foil airbags, where a series of sheets of metal are formed into an inflatable pressure vessel.
In order to avoid fastener openings in the airbag, fastener openings have been pushed to the perimeter of the airbags. However, by pushing the fastener openings to the perimeter of the airbag, the opening in the instrument panel for the airbag module must be increased. Large openings in the instrument panel can also have a poor appearance. Alternatively, the airbag may be folded into a smaller outline and bulkier depth to fit within a smaller area. However, the bulk of the airbag may require a deeper opening in the instrument panel and may also interfere with deployment of the airbag.
Therefore, what is needed in the art is an instrument panel mountable airbag module that has no fastener openings in the cover. What is also needed in the art is a mounting system for attaching a knee bolstering airbag employing snap-locking fasteners. What is further need in the art is a knee bolstering airbag that is positionable on a base member independent of the position of the fasteners.
There is a further need in the art for knee bolstering airbag that is attachable to an instrument panel with minimal steps and tools. There is also a need for a knee bolstering airbag attachment system that is attachable with snap-locking fasteners. A need further exists for an airbag module that minimizes rattling of the airbag module. Such an attachment system and airbag module are disclosed herein.